The Program for the Elimination of Cancer Disparities (PECaD) at the Alvin J. Siteman Cancer Center (SCC) of Washington University School of Medicine (WUSM) and Barnes-Jewish Hospital (BJH) has enabled enhanced research and training to be conducted in the areas of clinical and translational science and research, with a focus on community-based participatory research (CBPR) in St. Louis, and beyond. Although it did not have a formal training program, an important contribution of PECaD during previous funding has been the formal and informal mentoring of a diverse group of junior investigators on our campus and throughout the nation. With this application, we plan to build on PECaD's strong track record, formalize its training of the most promising participants in transdisciplinary CBPR, and focus especially on cross-training of academics and community partners. We shall leverage our established transdisciplinary connections within the superb clinical the rich community ties and resources in underserved neighborhoods in St. Louis. The goal for this new Transdisciplinary Community-Based Participatory Research (TCBPR) Training Program is to produce accomplished transdisciplinary researchers capable of utilizing the tools of community-based, clinical, and basic research to establish independent research programs in the service of underserved patients and communities. Toward this goal, the program primarily will assist junior faculty, junior investigators (postdoctoral and predoctoral researchers) and students (undergraduate and graduate) in their career development, yet we also will institute training among senior investigators across the campus to develop and enrich their knowledge about, and research and focus on, transdisciplinary CBPR approaches to reduce cancer disparities. While training will be tailored to the individual trainee, we will aim to inform broadly across the University community. We have developed a selection process for individual trainees that is transparent and a transdisciplinary mentoring process that ensures wider participation by a diverse group of trainees and mentors as detailed below.